Re: [PATCH] x86: UV: raw_spinlock conversion

From: Thomas Gleixner
Date: Sun May 06 2018 - 06:27:06 EST


On Fri, 4 May 2018, Sebastian Andrzej Siewior wrote:

> From: Mike Galbraith <umgwanakikbuti@xxxxxxxxx>
>
> Shrug. Lots of hobbyists have a beast in their basement, right?

This hardly qualifies as a proper changelog ...

> }
> @@ -299,13 +299,17 @@ static int uv_rtc_unset_timer(int cpu, i
> static u64 uv_read_rtc(struct clocksource *cs)
> {
> unsigned long offset;
> + u64 cycles;
>
> + preempt_disable();
> if (uv_get_min_hub_revision_id() == 1)
> offset = 0;
> else
> offset = (uv_blade_processor_id() * L1_CACHE_BYTES) % PAGE_SIZE;
>
> - return (u64)uv_read_local_mmr(UVH_RTC | offset);
> + cycles = (u64)uv_read_local_mmr(UVH_RTC | offset);
> + preempt_enable();
> + return cycles;

And how exaclty is this hunk related?

Thanks,

tglx